In This Package:

HepMC::FourVector Class Reference

For compatibility with existing code, the basic expected geometrical access methods are povided. More...

#include <SimpleVector.h>

List of all members.

Public Member Functions
	FourVector (double xin, double yin, double zin, double tin=0)
	constructor requiring at least x, y, and z
	FourVector (double t)
	constructor requiring only t
	FourVector ()
template<class T>
	FourVector (const T &v, typename detail::disable_if< detail::is_arithmetic< T >::value, void >::type *=0)
	templated constructor this is used ONLY if T is not arithmetic
	FourVector (const FourVector &v)
	copy constructor
void	swap (FourVector &other)
	swap
double	px () const
	return px
double	py () const
	return py
double	pz () const
	return pz
double	e () const
	return E
double	x () const
	return x
double	y () const
	return y
double	z () const
	return z
double	t () const
	return t
double	m2 () const
	Invariant mass squared.
double	m () const
	Invariant mass. If m2() is negative then -sqrt(-m2()) is returned.
double	perp2 () const
	Transverse component of the spatial vector squared.
double	perp () const
	Transverse component of the spatial vector (R in cylindrical system).
double	mag () const
	Magnitude of the spatial vector.
double	theta () const
	The polar angle.
double	phi () const
	The azimuth angle.
double	rho () const
	spatial vector component magnitude
FourVector &	operator= (const FourVector &)
	make a copy
bool	operator== (const FourVector &) const
	equality
bool	operator!= (const FourVector &) const
	inequality
double	pseudoRapidity () const
	Returns the pseudo-rapidity, i.e. -ln(tan(theta/2)).
double	eta () const
	Pseudorapidity (of the space part).
void	set (double x, double y, double z, double t)
	set x, y, z, and t
void	setX (double x)
	set x
void	setY (double y)
	set y
void	setZ (double z)
	set z
void	setT (double t)
	set t
void	setPx (double x)
	set px
void	setPy (double y)
	set py
void	setPz (double z)
	set pz
void	setE (double t)
	set E
Private Attributes
double	m_x
double	m_y
double	m_z
double	m_t

---

Detailed Description

For compatibility with existing code, the basic expected geometrical access methods are povided.

Also, there is a templated constructor that will take another vector (HepLorentzVector, GenVector, ...) which must have the following methods: x(), y(), z(), t().

Definition at line 42 of file SimpleVector.h.

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Constructor & Destructor Documentation

HepMC::FourVector::FourVector	(	double	xin,
		double	yin,
		double	zin,
		double	tin = 0
	)			[inline]

constructor requiring at least x, y, and z

Definition at line 47 of file SimpleVector.h.

  : m_x(xin), m_y(yin), m_z(zin), m_t(tin) {}

HepMC::FourVector::FourVector

(

double

t

)

[inline]

constructor requiring only t

Definition at line 51 of file SimpleVector.h.

  : m_x(0), m_y(0), m_z(0), m_t(t) {}

HepMC::FourVector::FourVector

(

)

[inline]

Definition at line 54 of file SimpleVector.h.

  : m_x(0), m_y(0), m_z(0), m_t(0) {}

template<class T>

HepMC::FourVector::FourVector	(	const T &	v,
		typename detail::disable_if< detail::is_arithmetic< T >::value, void >::type *	= 0
	)			[inline]

templated constructor this is used ONLY if T is not arithmetic

Definition at line 60 of file SimpleVector.h.

  : m_x(v.x()), m_y(v.y()), m_z(v.z()), m_t(v.t()) {}

HepMC::FourVector::FourVector

(

const FourVector &

v

)

[inline]

copy constructor

Definition at line 65 of file SimpleVector.h.

  : m_x(v.x()), m_y(v.y()), m_z(v.z()), m_t(v.t()) {}

---

Member Function Documentation

void HepMC::FourVector::swap

(

FourVector &

other

)

[inline]

swap

Definition at line 20 of file SimpleVector.icc.

                                                 {
    std::swap( m_x, other.m_x );
    std::swap( m_y, other.m_y );
    std::swap( m_z, other.m_z );
    std::swap( m_t, other.m_t );
}

double HepMC::FourVector::px

(

)

const [inline]

return px

Definition at line 70 of file SimpleVector.h.

double HepMC::FourVector::py

(

)

const [inline]

return py

Definition at line 71 of file SimpleVector.h.

double HepMC::FourVector::pz

(

)

const [inline]

return pz

Definition at line 72 of file SimpleVector.h.

double HepMC::FourVector::e

(

)

const [inline]

return E

Definition at line 73 of file SimpleVector.h.

double HepMC::FourVector::x

(

)

const [inline]

return x

Definition at line 75 of file SimpleVector.h.

double HepMC::FourVector::y

(

)

const [inline]

return y

Definition at line 76 of file SimpleVector.h.

double HepMC::FourVector::z

(

)

const [inline]

return z

Definition at line 77 of file SimpleVector.h.

double HepMC::FourVector::t

(

)

const [inline]

return t

Definition at line 78 of file SimpleVector.h.

double HepMC::FourVector::m2

(

)

const [inline]

Invariant mass squared.

Definition at line 42 of file SimpleVector.icc.

                                   {
  return m_t*m_t - (m_x*m_x + m_y*m_y + m_z*m_z);
}

double HepMC::FourVector::m

(

)

const [inline]

Invariant mass. If m2() is negative then -sqrt(-m2()) is returned.

Definition at line 46 of file SimpleVector.icc.

                                  {
  double mm = m2();
  return mm < 0.0 ? -std::sqrt(-mm) : std::sqrt(mm);
}

double HepMC::FourVector::perp2

(

)

const [inline]

Transverse component of the spatial vector squared.

Definition at line 55 of file SimpleVector.icc.

{ return m_x*m_x + m_y*m_y; }

double HepMC::FourVector::perp

(

)

const [inline]

Transverse component of the spatial vector (R in cylindrical system).

Definition at line 57 of file SimpleVector.icc.

{ return std::sqrt(perp2()); }

double HepMC::FourVector::mag

(

)

const [inline]

Magnitude of the spatial vector.

Definition at line 51 of file SimpleVector.icc.

                                     { 
return std::sqrt( m_x*m_x + m_y*m_y + m_z*m_z );
}

double HepMC::FourVector::theta

(

)

const [inline]

The polar angle.

Definition at line 59 of file SimpleVector.icc.

                                         {
  return m_x == 0.0 && m_y == 0.0 && m_z == 0.0 ? 0.0 : std::atan2(perp(),m_z);
}

double HepMC::FourVector::phi

(

)

const [inline]

The azimuth angle.

Definition at line 63 of file SimpleVector.icc.

                                    {
  return m_x == 0.0 && m_y == 0.0 ? 0.0 : std::atan2(m_y,m_x);
}

double HepMC::FourVector::rho

(

)

const [inline]

spatial vector component magnitude

Definition at line 67 of file SimpleVector.icc.

                                     { 
return std::sqrt( m_x*m_x + m_y*m_y + m_z*m_z );
}

FourVector & HepMC::FourVector::operator=

(

const FourVector &

)

[inline]

make a copy

Definition at line 27 of file SimpleVector.icc.

                                                              {
  m_x = v.x();
  m_y = v.y();
  m_z = v.z();
  m_t = v.t();
  return *this;
}

bool HepMC::FourVector::operator==

(

const FourVector &

)

const [inline]

equality

Definition at line 71 of file SimpleVector.icc.

                                                               {
  return (v.x()==x() && v.y()==y() && v.z()==z() && v.t()==t()) ? true : false;
}

bool HepMC::FourVector::operator!=

(

const FourVector &

)

const [inline]

inequality

Definition at line 75 of file SimpleVector.icc.

                                                               {
  return (v.x()!=x() || v.y()!=y() || v.z()!=z() || v.t()!=t()) ? true : false;
}

double HepMC::FourVector::pseudoRapidity

(

)

const [inline]

Returns the pseudo-rapidity, i.e. -ln(tan(theta/2)).

Definition at line 79 of file SimpleVector.icc.

                                               {
  double m = mag();
  if ( m==  0   ) return  0.0;   
  if ( m==  z() ) return  1.0E72;
  if ( m== -z() ) return -1.0E72;
  return 0.5*log( (m+z())/(m-z()) );
}

double HepMC::FourVector::eta

(

)

const [inline]

Pseudorapidity (of the space part).

Definition at line 87 of file SimpleVector.icc.

{ return pseudoRapidity();}

void HepMC::FourVector::set	(	double	x,
		double	y,
		double	z,
		double	t
	)			[inline]

set x, y, z, and t

Definition at line 35 of file SimpleVector.icc.

                                                                   {
  m_x = x;
  m_y = y;
  m_z = z;
  m_t = t;
}

void HepMC::FourVector::setX

(

double

x

)

[inline]

set x

Definition at line 103 of file SimpleVector.h.

void HepMC::FourVector::setY

(

double

y

)

[inline]

set y

Definition at line 104 of file SimpleVector.h.

void HepMC::FourVector::setZ

(

double

z

)

[inline]

set z

Definition at line 105 of file SimpleVector.h.

void HepMC::FourVector::setT

(

double

t

)

[inline]

set t

Definition at line 106 of file SimpleVector.h.

void HepMC::FourVector::setPx

(

double

x

)

[inline]

set px

Definition at line 108 of file SimpleVector.h.

void HepMC::FourVector::setPy

(

double

y

)

[inline]

set py

Definition at line 109 of file SimpleVector.h.

void HepMC::FourVector::setPz

(

double

z

)

[inline]

set pz

Definition at line 110 of file SimpleVector.h.

void HepMC::FourVector::setE

(

double

t

)

[inline]

set E

Definition at line 111 of file SimpleVector.h.

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Member Data Documentation

double HepMC::FourVector::m_x [private]

Definition at line 115 of file SimpleVector.h.

double HepMC::FourVector::m_y [private]

Definition at line 116 of file SimpleVector.h.

double HepMC::FourVector::m_z [private]

Definition at line 117 of file SimpleVector.h.

double HepMC::FourVector::m_t [private]

Definition at line 118 of file SimpleVector.h.

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The documentation for this class was generated from the following files:

• /home/dayabay/installs/trunk_2011_04_11_opt/external/HepMC/2.03.09/i686-slc5-gcc41-opt/include/HepMC/SimpleVector.h
• /home/dayabay/installs/trunk_2011_04_11_opt/external/HepMC/2.03.09/i686-slc5-gcc41-opt/include/HepMC/SimpleVector.icc

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